docs: capture the SQL the other node actually runs, and correct the replication claim

PostgreSQL statement logging shows keycloak-1 reading and updating the session created on keycloak-0. The same transaction reveals optimistic locking via VERSION, SKIP LOCKED, and synchronous_commit turned off. Fixes the earlier concept note that credited Infinispan with cross-node propagation.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This commit is contained in:
DongHyeonka
2026-09-04 10:14:45 +09:00
co-authored by Claude Opus 5
parent e5ebaeb623
commit 22d873eb4f
5 changed files with 359 additions and 23 deletions
@@ -0,0 +1,56 @@
===================================================================
실험 0d — 반대편 노드가 정말 DB 에서 읽는가 (SQL 을 직접 잡는다)
===================================================================
수집 시각: 2026-09-04 10:14:17 KST
keycloak-0 = 10.42.1.43 (세션을 만드는 노드)
keycloak-1 = 10.42.0.35 (읽기만 하는 노드)
=== PostgreSQL 문장 로깅을 켠다 ===
log_statement = all
log_line_prefix = %m [%p] %h
=== 요청 ===
SID=jSt9GEPVQLJsO-1CeJjVgltg
K1_ENTRIES_BEFORE=5.0
REFRESH_ON_K1=200
K1_ENTRIES_AFTER=5.0
=== PostgreSQL 문장 로깅을 끈다 ===
log_statement = none
=== keycloak-1 이 실제로 보낸 SQL 문장 ===
(파라미터가 $1 로 묶여 있어, sid 는 바로 아래 DETAIL 줄에 있다)
select puse1_0.OFFLINE_FLAG,puse1_0.USER_SESSION_ID,puse1_0.BROKER_SESSION_ID,puse1_0.CREATED_ON,puse1_0.DATA,puse1_0.LAST_SESSION_REFRESH,puse1_0.REALM_ID,puse1_0.REMEMBER_ME,puse1_0.USER_ID,puse1_0.VERSION from OFFLINE_USER_SESSION puse1_0 where (puse1_0.OFFLINE_FLAG,puse1_0.USER_SESSION_ID) in (($1,$2))
select puse1_0.VERSION from OFFLINE_USER_SESSION puse1_0 where puse1_0.USER_SESSION_ID=$1 and puse1_0.OFFLINE_FLAG=$2 for no key update of puse1_0 skip locked
select pcse1_0.CLIENT_ID,pcse1_0.CLIENT_STORAGE_PROVIDER,pcse1_0.EXTERNAL_CLIENT_ID,pcse1_0.OFFLINE_FLAG,pcse1_0.USER_SESSION_ID,pcse1_0.DATA,pcse1_0.REALM_ID,pcse1_0.TIMESTAMP,pcse1_0.VERSION from OFFLINE_CLIENT_SESSION pcse1_0 where (pcse1_0.CLIENT_ID,pcse1_0.CLIENT_STORAGE_PROVIDER,pcse1_0.EXTERNAL_CLIENT_ID,pcse1_0.OFFLINE_FLAG,pcse1_0.USER_SESSION_ID) in (($1,$2,$3,$4,$5))
select pcse1_0.VERSION from OFFLINE_CLIENT_SESSION pcse1_0 where pcse1_0.USER_SESSION_ID=$1 and pcse1_0.OFFLINE_FLAG=$2 and pcse1_0.CLIENT_ID=$3 and pcse1_0.EXTERNAL_CLIENT_ID=$4 and pcse1_0.CLIENT_STORAGE_PROVIDER=$5 for no key update of pcse1_0 skip locked
update OFFLINE_CLIENT_SESSION set TIMESTAMP=$1,VERSION=$2 where CLIENT_ID=$3 and CLIENT_STORAGE_PROVIDER=$4 and EXTERNAL_CLIENT_ID=$5 and OFFLINE_FLAG=$6 and USER_SESSION_ID=$7 and VERSION=$8
update OFFLINE_USER_SESSION set LAST_SESSION_REFRESH=$1,VERSION=$2 where OFFLINE_FLAG=$3 and USER_SESSION_ID=$4 and VERSION=$5
SET LOCAL synchronous_commit TO OFF
COMMIT
DELETE from JGROUPS_PING WHERE address=$1
INSERT INTO JGROUPS_PING (address, name, cluster_name, ip, coord, last_update, coordinated_by) values ($1, $2, $3, $4, $5, $6, $7)
COMMIT
DELETE from JGROUPS_PING WHERE address=$1
=== 그 sid 를 언급한 SQL — 누가 보냈는가 ===
찾는 sid: jSt9GEPVQLJsO-1CeJjVgltg
2026-09-04 01:12:32.851 UTC [81407] [keycloak-0] DETAIL: parameters: $1 = '0', $2 = 'jSt9GEPVQLJsO-1CeJjVgltg'
2026-09-04 01:12:32.852 UTC [81407] [keycloak-0] DETAIL: parameters: $1 = '131a9912-b578-4b9c-b16a-97518704077e', $2 = 'local', $3 = 'local', $4 = '0', $5 = 'jSt9GEPVQLJsO-1CeJjVgltg'
2026-09-04 01:12:32.860 UTC [81407] [keycloak-0] DETAIL: parameters: $1 = '0', $2 = 'jSt9GEPVQLJsO-1CeJjVgltg'
2026-09-04 01:12:32.862 UTC [81407] [keycloak-0] DETAIL: parameters: $1 = '131a9912-b578-4b9c-b16a-97518704077e', $2 = 'local', $3 = 'local', $4 = '0', $5 = 'jSt9GEPVQLJsO-1CeJjVgltg'
2026-09-04 01:12:32.863 UTC [81407] [keycloak-0] DETAIL: parameters: $1 = NULL, $2 = '1788484352', $3 = '{"ipAddress":"10.42.1.50","authMethod":"openid-connect","rememberMe":false,"started":0,"notes":{"KC_DEVICE_NOTE":"
2026-09-04 01:12:32.864 UTC [81407] [keycloak-0] DETAIL: parameters: $1 = '{"authMethod":"openid-connect","notes":{"clientId":"131a9912-b578-4b9c-b16a-97518704077e","userSessionStartedAt":"1788484352","iss":"https://aut
2026-09-04 01:12:34.934 UTC [81376] [keycloak-1] DETAIL: parameters: $1 = '0', $2 = 'jSt9GEPVQLJsO-1CeJjVgltg'
2026-09-04 01:12:34.936 UTC [81376] [keycloak-1] DETAIL: parameters: $1 = 'jSt9GEPVQLJsO-1CeJjVgltg', $2 = '0'
2026-09-04 01:12:34.937 UTC [81376] [keycloak-1] DETAIL: parameters: $1 = '131a9912-b578-4b9c-b16a-97518704077e', $2 = 'local', $3 = 'local', $4 = '0', $5 = 'jSt9GEPVQLJsO-1CeJjVgltg'
2026-09-04 01:12:34.938 UTC [81376] [keycloak-1] DETAIL: parameters: $1 = 'jSt9GEPVQLJsO-1CeJjVgltg', $2 = '0', $3 = '131a9912-b578-4b9c-b16a-97518704077e', $4 = 'local', $5 = 'local'
2026-09-04 01:12:34.944 UTC [81376] [keycloak-1] DETAIL: parameters: $1 = '1788484354', $2 = '1', $3 = '131a9912-b578-4b9c-b16a-97518704077e', $4 = 'local', $5 = 'local', $6 = '0', $7 = 'jSt9GEPVQLJsO-1CeJjVgltg', $8 =
2026-09-04 01:12:34.946 UTC [81376] [keycloak-1] DETAIL: parameters: $1 = '1788484354', $2 = '1', $3 = '0', $4 = 'jSt9GEPVQLJsO-1CeJjVgltg', $5 = '0'
=== 요약: 파드별 질의 건수 ===
6 [keycloak-1]
6 [keycloak-0]
@@ -15,3 +15,12 @@
클러스터는 형성되지만 **세션 엔트리는 노드를 건너가지 않는다.**
두 노드가 같은 답을 하는 이유는 Infinispan 복제가 아니라 **같은 PostgreSQL** 이다.
| 파일 | 무엇을 보여주는가 |
|---|---|
| `04-read-path-sql.txt` | PostgreSQL 문장 로깅으로 잡은 **keycloak-1 이 실제로 날린 SQL**. `SELECT ... FROM OFFLINE_USER_SESSION` 로 남의 세션을 읽고 `UPDATE ... where VERSION=$5` 로 쓴다. 같은 트랜잭션에 `SET LOCAL synchronous_commit TO OFF` 가 들어 있다 |
## 추론이 관측이 된 지점
0b·0c 는 "keycloak-1 메모리에 없는데 쓸 수 있으니 DB 에서 읽었을 것"이라는
**추론**이었다. 0d 에서 그 SQL 을 파드 IP 와 함께 직접 잡았다.